Revert "Stop trying to show the original value"

This reverts commit 8c9c0db.

Author: DanielEScherzer

ext/filter/filter.c

@@ -280,16 +280,28 @@ static void php_zval_filter(zval *value, zend_long filter, zend_long flags, zval
 	/* Here be strings */
 	convert_to_string(value);
 
+	zend_string *copy_for_throwing = NULL;
+	if (flags & FILTER_THROW_ON_FAILURE) {
+		copy_for_throwing = zend_string_copy(Z_STR_P(value));
+	}
+
 	zend_result result = filter_func.function(value, flags, options, charset);
 
-	if ((flags & FILTER_THROW_ON_FAILURE) && result == FAILURE) {
-		zend_throw_exception_ex(
-			php_filter_failed_exception_ce,
-			0,
-			"filter validation failed: filter %s not satisfied",
-			filter_func.name
-		);
-		return;
+	if (flags & FILTER_THROW_ON_FAILURE) {
+		ZEND_ASSERT(copy_for_throwing != NULL);
+		if (result == FAILURE) {
+			zend_throw_exception_ex(
+				php_filter_failed_exception_ce,
+				0,
+				"filter validation failed: filter %s not satisfied by %s",
+				filter_func.name,
+				ZSTR_VAL(copy_for_throwing)
+			);
+			zend_string_delref(copy_for_throwing);
+			return;
+		}
+		zend_string_delref(copy_for_throwing);
+		copy_for_throwing = NULL;
 	}
 
 handle_default:

ext/filter/tests/throw-on-failure/filter_input_array_failure.phpt

@@ -26,4 +26,4 @@ validation fails (array type check)
 Filter\FilterFailedException: filter validation failed: not an array (got string)
 
 validation fails (filter value)
-Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied
+Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied by 1

ext/filter/tests/throw-on-failure/filter_input_failure.phpt

@@ -36,4 +36,4 @@ validation fails (array type check)
 Filter\FilterFailedException: filter validation failed: not an array (got string)
 
 validation fails (filter value)
-Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied
+Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied by 1

ext/filter/tests/throw-on-failure/filter_var_array_failure.phpt

@@ -36,4 +36,4 @@ validation fails (object without __toString)
 Filter\FilterFailedException: filter validation failed: object of type stdClass has no __toString() method
 
 validation fails (filter value)
-Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied
+Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied by 1

ext/filter/tests/throw-on-failure/filter_var_failure.phpt

@@ -34,4 +34,4 @@ validation fails (object without __toString)
 Filter\FilterFailedException: filter validation failed: object of type stdClass has no __toString() method
 
 validation fails (filter value)
-Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied
+Filter\FilterFailedException: filter validation failed: filter validate_email not satisfied by a